Abstract (Summary)
Performance of a mobile ad hoc network (MANET) depends directly on the quality of routes selected by the routing protocol at the network layer and the packet transmission efficiency of the MAC layer protocol. The network layer routing protocol used in a MANET does not truly reflect the exact network topology as there is always a delay between topology changes in the network due to user’s mobility and its corresponding routing table changes at the network layer by the routing protocol. Therefore, high user mobility in MANETs causes frequent link breaks when a pair of mobile user nodes, which have moved out of the transmission range of each other but are still shown as neighbors by the routing table, try to communicate with each other. This causes several unnecessary retransmissions between them at the MAC layer before the link is declared dead. Such retransmissions result in inefficient network resource utilization as power and bandwidth are wasted in transmission attempts by the sender node to send packet to the out-of-range receiver node. This research work proposes enhancements for the MAC layer protocol with associated changes at the network layer routing protocol that reduce link break probability, collision probability faced by a transmission, and solve the channel under-utilization problem because of the exposed terminal problem. The proposed schemes, i.e., location prediction check, transmission awareness and service differentiation, use current ongoing transmission information contained in the MAC layer protocol’s handshake packets with piggybacked transmitting node’s mobility-location information. A higher overall performance is achieved with the proposed implementation of the routing protocol over the MAC layer protocol in terms of throughput, power utilization and better quality of service (QoS).
Bibliographical Information:


School:University of Cincinnati

School Location:USA - Ohio

Source Type:Master's Thesis

Keywords:ad hoc networks dsdv routing protocol csma ca mac cross layer location prediction techniques exposed terminal problem


Date of Publication:01/01/2005

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